Wind turbine blades are often provided with a bulkhead arranged at the root end of the blade. The bulkhead is generally used to provide a work platform for workers carrying out maintenance or repair on the blade, and to prevent internal debris and fluids such as water or oil from passing between the internal blade cavity and the wind turbine rotor hub and machine housing.
The bulkhead may be flexibly mounted to the internal wall of the wind turbine blade using a flexible mounting flange, an example of which can be seen in WO 2012/119934. Alternatively, the bulkhead may be rigidly mounted to the internal wall. A sealing member may be located around the periphery of the bulkhead, to ensure that the bulkhead is watertight.
One issue with such current wind turbine blade bulkhead arrangements is that cracks or faults may be observed in the mounting flanges and/or sealing members over time, thereby compromising the integrity of the bulkhead mounting and the effectiveness of the sealing properties of the bulkhead. It is thought that such faults are the result of centrifugal forces acting on the flanges and/or sealing members, blade deformations due to wind loads, and pressure differentials between opposed sides of the bulkhead.
Such cracks or faults must be repaired to ensure operational effectiveness of the wind turbine. The current approach to mitigating such problems is the construction of stronger mounting flanges and/or sealing members, resulting in an increase in blade costs and/or weight.
Accordingly, it is an object of the invention to provide a bulkhead system for a wind turbine blade having improved resistance to operational defects such as crack or fault formation in the bulkhead mounting flanges and/or sealing members.